Information recording medium, information recording/reproducing method, and information recording/reproducing device

ABSTRACT

A lead-out area is recorded and a session is formed each time a file is recorded with the data structure of a disc recorded with the conventional CD-R multi-session method. The latest file structure recorded in the last session is read with a multi-session disc by reading in series the start address of the next session recorded in the lead-in area of each session. This information read in series is dependent upon the number of file write operations, and as the number of writes increases, the slower the latest file structure retrieval process becomes. In a write-once medium in which the file management information and unrecorded area information are update recorded at each recording session, chaining information is recorded at each file write. Furthermore, an area for recording a plurality of continuously recorded chaining information is reserved, and access in the latest chaining information retrieval process is accelerated. Furthermore, address information for an area contiguously reserved for chaining information is recorded in part of the chaining information.

TECHNICAL FIELD

The present invention relates to a data storage medium to which filesmanaged using a volume/file structure are recorded and reproduced, andin which the number of data recording operations to any same area islimited, and to a data recording and reproducing method and datarecording and reproducing apparatus using this data storage medium. Moreparticularly, the present invention relates to a data storage mediumhaving a volume/file structure for retrieving the latest file managementinformation, which is recorded continuously in the space in fileaddition units for managing file information and address information forunrecorded areas in the volume space and can be reproduced in series tomake access faster, and relates to a data recording and reproducingmethod and a data recording and reproducing apparatus using this datastorage medium.

BACKGROUND ART

While media of various types have been used in recent years forrecording digital data, CD-R discs in particular have quickly becomecommonly used as a low-cost recordable optical disc medium. Themulti-session method is now well known as a technique for writing datato these CD-R discs; a data recording operation using this multi-sessionmethod is described next below with reference to the accompanyingfigures.

FIG. 14 shows the data structure of a CD-R disc to which files managedusing the volume/file structure defined in the ISO 9660 standard arerecorded using a multi-session method. In a multi-session recordingmethod, files and file structure and volume structure for managing filesare recorded in session units. Each session has a lead-in area, an innerlink area, a user data area, and a lead-out area. It is to be noted thatonly the first session does not have a lead-in area; an outer link areais formed between sessions.

When recording data by session unit, a file and file structure andvolume structure for managing the file are first recorded to the userdata area. In order to make data reproduction easier for a CD-ROM drive,which is unable to detect a location in a unrecorded area of a CD-R discbecause it is unable to detect the wobble address recorded to the CD-Rdisc, data containing address information is also recorded to thelead-out area, and data containing start address information for thenext session is recorded to a lead-in area, when the CD-R disc isremoved from the CD-R drive. The user area, lead-in area, and lead-outarea are each recorded in separate data recording operations. The datarecorded in the data recording operation for each area is the recordingdata with a link block and run-in block, or a run-out block and linkblock, added therebefore and thereafter. An inner link area or an outerlink area comprising a run-out block, link block, and run-in block isthus formed at the junction between these areas.

A multi-session data recording operation is described next below. FIG.15 shows the directory structure used for managing files recorded to aCD-R disc. The directory structure shown in FIG. 15 has a subdirectory(Dir-A) for managing a data file (File-a), a subdirectory (Dir-B) formanaging a data file (File-b), and a subdirectory (Dir-C) for managing adata file (File-c) below the root directory. When data file (File-a),data file (File-b), and data file (File-c) are recorded during a firstsession, second session, and third session in accordance with thisdirectory structure, the data structure described above with referenceto FIG. 14 is formed on the CD-R disc.

FIG. 16 is a flow chart describing a recording operation for creating adisc with the data structure shown in FIG. 15. The data recordingoperation performed each session is described next below according tothe steps shown in this flow chart.

(S1601) When a CD-R disc is inserted into the disc recorder, the discrecorder accesses the lead-in area reserved at a specific location atthe inside circumference of the disc, and attempts to read the TOC datafrom this lead-in area. If the TOC data is reproduced from the lead-inarea, a step (S1602) for retrieving the following session data isperformed. However, if the data could not be reproduced because thelead-in area is unrecorded, the session data recording operation isperformed according to the procedure beginning in step (S1603).

(S1602) If the TOC data is reproduced from the lead-in area, the discrecorder reads the start address of the following session contained inthis TOC data, returns to step (S1601), and then tries to reproduce datafrom the lead-in area of the following session.

(S1603) When a lead-in area to which no data is recorded is detected,the file recorded as the session data and the file structure and volumestructure for managing said file are generated as follow.

First, when data is not reproduced from the first lead-in area, the datafile (File-a) to be recorded as the data for the first session,subdirectory (Dir-A) for managing data file (File-a) and a directoryfile for managing the root directory, and volume/file structure, such asa primary volume descriptor and path table, for managing these files andthe directory file, are generated according to the ISO 9660 standard.

If TOC data is reproduced from the first lead-in area, the volume/filestructure and directory file are read using the user data area startaddress contained in the last read TOC data. For example, with a disc towhich only a first session has been recorded, data is read from userdata area 1402; with a disc that has been recorded through a secondsession, data is read from user data area 1405. The content of thevolume/file structure is then updated by adding the file to be recordedand a directory file for managing said file to the read data. Forexample, a new volume/file structure is generated data by adding file(File-b) and the directory file (Dir-B) of the subdirectory for managingdata file (File-b) to the data read from user data area 1402 on a discto which only a first session has been recorded; and by adding data file(File-c) and the directory file (Dir-C) of the subdirectory for managingdata file (File-c) to the data read from user data area 1405 on a discto which a second session has also been recorded.

(S1604) When the volume/file structure to be recorded to a user dataarea is generated, a lead-in area and run-out block of predeterminedrecording size are skipped, and the recording data generated in step(S1603) to which a predefined link block/run-in block and linkblock/run-out block have been added therebefore and thereafter iscontinuously recorded.

(S1605) When data recording to the user data area is completed,recording data having a predefined link block/run-in block and linkblock/run-out block added before and after the data recorded to thelead-out area is generated. The resulting recording data is thenrecorded continuously from the link block following the run-out blockrecorded in step (S1604). When recording the first session, for example,this operation records lead-out area 1403 and the link block/run-inblock and run-out block/link block located therebefore and thereafter.When recording a second session, this operation records lead-out area1406 and the link block/run-in block and run-out block/link blocklocated therebefore and thereafter.

(S1606) When data recording to the lead-out area is completed, the startaddress of the next session is calculated with consideration for thepredetermined recording size of the outer link area. The calculatedstart address of the next session is then embedded in the TOC datarecorded to the lead-in area together with the start address for theuser data area recorded in step (S1604).

Recording data comprising predefined link block/run-in block and run-outblock/link block units before and after the recording data for thelead-in area is then generated. The resulting recording data is thenrecorded continuously from a specific position at the insidecircumference of the disc if the first session is being recorded. As aresult of this recording operation, lead-in area 1401 and the run-outblock/link block located immediately thereafter are recorded in therecording operation for a first session, for example. In a recordingoperation for a second session, the lead-in area 1404 and the linkblock/run-in block and run-out block/link block units positionedtherebefore and thereafter are recorded, and the data recordingoperation ends.

The data recording operation described above forms a multi-session datastructure such as shown in FIG. 14 on the disc. A logical sector number(LSN) is assigned to each sector in the data structure shown in FIG. 14with the first sector in the user data area in the first sessiondesignated 0, and the logical sector number rising continuously at eachsuccessive sector. The volume space is defined as the area beginningfrom the sector at LSN 0.

The operation whereby a data file (File-a) is reproduced from the firstsession of a disc having a data structure as shown in FIG. 14 isdescribed next below with reference to FIG. 14 and FIG. 16.

When a CD-R disc is inserted to a disc reader, the disc reader followsthe procedure shown in steps (S1601) to (S1603) in the flow chart inFIG. 16 to read the latest volume/file structure 1420 from the user dataarea of the third session. If a CD-ROM drive is connected to a computersystem, the host computer obtains the start address for the user dataarea of the third session to which the latest volume/file structure isrecorded by executing a READ TOC command. Using this start address, itthen calculates the LSN of the sector to which the latest volume/filestructure is recorded, and reads this structure from the disc.

Next, when the latest volume/file structure 1420 is read, the structureis interpreted according to the ISO 9660 standard using the primaryvolume descriptor 1421, path table 1422, root directory 1423, anddirectory file (Dir-A) 1424 for managing data file (File-a) 1425. Therecording position of the data file is then read from the directoryrecord of the data file (File-a) 1425 contained in directory file(Dir-A) 1424.

The data file (File-a) 1425 recorded to the user data area of the firstsession is then reproduced based on said data file recording position.

DISCLOSURE OF INVENTION Technical Problem to be Solved by the Invention

With the multi-session method as described above, a lead-out area mustbe recorded to form a session each time a file is recorded.

Furthermore, with the data structure of a disc recorded using thismulti-session method, the latest file structure recorded to the lastsession is read by reading in series the address information of thefollowing session from the lead-in area of each session, starting fromthe address information of the next session recorded to the lead-in areaof the first session.

In addition, this address information reading operation must beaccomplished by running a READ TOC command or other special commandinstead of using the standard READ command used for reproducing filesfrom the volume space. The present invention solves the above-notedproblem, and has as an object enabling writing in file units withoutrequiring a finalizing process such as recording a lead-out area eachtime a file is written, and enabling the latest file structure to beread at high speed using a standard READ command.

Method of Solving the Problem

The above noted object is achieved by a data structure such as that of adata storage medium in which a file managed using a volume/filestructure is recorded and reproduced from one end of a data recordingarea, and in which a number of data recording operations to a same areais limited, wherein the data storage medium is characterized by an areafor continuously recording a plurality of chaining information areas towhich is recorded chaining information containing root directory filemanagement information having location information for a next rootdirectory file allocated for update recording, and unallocated areamanagement information having location information for a next unrecordedarea.

The above noted object is achieved by a processing sequence such as thatof a data recording method for applying a formatting process to a datastorage medium in which a file managed using a volume/file structure isrecorded and reproduced from one end of a data recording area, and inwhich a number of data recording operations to a same area is limited,the data recording method characterized by a volume structure recordingstep for recording volume structure; an open integrity informationrecording step for recording open integrity information indicating aformatting process start status; an unallocated chaining informationarea address calculation and registration step for calculating andregistering in chaining information an address of an unallocatedchaining information area that is an unallocated area in an area wherechaining information is continuously recorded; a root directory filerecording step for recording a root directory file; and a chaininginformation recording step for recording chaining information.

The above noted object is achieved by a processing means such as that ofa data recording apparatus for applying a formatting process to a datastorage medium in which a file managed using a volume/file structure isrecorded and reproduced from one end of a data recording area, and inwhich a number of data recording operations to a same area is limited,the data recording apparatus characterized by a volume structurerecording means for recording volume structure; an open integrityinformation recording means for recording open integrity informationindicating a formatting process start status; an address calculation andregistration means for calculating and registering in chaininginformation an address of an unallocated chaining information area thatis an unallocated area in an area where chaining information iscontinuously recorded; a file structure recording means for recording aroot directory file; and a chaining information recording means forrecording chaining information.

The above noted object is achieved by a processing sequence such as thatof a data recording method for recording a file to a data storage mediumin which a file managed using a volume/file structure is recorded andreproduced from one end of a data recording area, and in which a numberof data recording operations to a same area is limited, the datarecording method characterized by a volume structure reproducing stepfor reading volume structure recorded in a formatting process; achaining information reproducing step for reading the latest chaininginformation while reading in series completely recorded chaininginformation according to previously read volume structure content; afile structure reproducing step for reading a file structure; a filerecording step for accomplishing data file recording; a file structurerecording step for accomplishing file structure recording; an addresscalculation and registration step for calculating and registering inchaining information an address of an unallocated chaining informationarea that is an unallocated area in an area where a plurality ofchaining information is continuously recorded; and a chaininginformation recording step for recording chaining information.

The above noted object is achieved by a processing means such as that ofa data recording apparatus for recording a file to a data storage mediumin which a file managed using a volume/file structure is recorded andreproduced from one end of a data recording area, and in which a numberof data recording operations to a same area is limited, the datarecording apparatus characterized by a volume structure reproducingmeans for reading volume structure recorded in a formatting process; achaining information reproducing means for reading the latest chaininginformation while reading in series completely recorded chaininginformation according to previously read volume structure content; afile structure reproducing means for reading a file structure; a filerecording means for accomplishing data file recording; a file structurerecording means for accomplishing file structure recording; an addresscalculation and registration means for calculating and registering inchaining information an address of an unallocated chaining informationarea that is an unallocated area in an area where a plurality ofchaining information is continuously recorded; and a chaininginformation recording for recording chaining information.

The above noted object is achieved by a processing sequence such as thatof a data recording method for applying a closing process, forpreventing a performance drop resulting from wrong access to anunrecorded area, to a data storage medium in which a file managed usinga volume/file structure is recorded and reproduced from one end of adata recording area, and in which a number of data recording operationsto a same area is limited, the data recording method characterized by avolume structure reproducing step for reading volume structure recordedin a formatting process; an integrity information reproducing step forreading the latest integrity information while reading in seriescompletely recorded close integrity information and open integrityinformation according to previously read volume structure content; achaining information reproducing step for reading the latest chaininginformation while reading in series completely recorded chaininginformation according to previously read volume structure content; afile structure reproducing step for reading a file structure using theread chaining information; an unallocated chaining information areaaddress calculation and registration step for calculating andregistering in chaining information an address of an unallocatedchaining information area that is an unallocated area in an area wherechaining information is continuously recorded; a chaining informationrecording step for recording chaining information; an overrun extentrecording step for recording an overrun extent for preventing wrongaccess to an unrecorded area in a file structure and file reproducingoperation; and a close integrity information recording step forrecording close integrity information indicative of recordingcompletion.

The above noted object is achieved by a processing means such as that ofa data recording apparatus for applying a closing process, forpreventing a performance drop resulting from wrong access to anunrecorded area, to a data storage medium in which a file managed usinga volume/file structure is recorded and reproduced from one end of adata recording area, and in which a number of data recording operationsto a same area is limited, the data recording apparatus characterized bya volume structure reproducing means for reading volume structurerecorded in a formatting process; an integrity information reproducingmeans for reading the latest integrity information while reading inseries completely recorded close integrity information and openintegrity information according to previously read volume structurecontent; a chaining information reproducing means for reading the latestchaining information while reading in series completely recordedchaining information according to previously read volume structurecontent; a file structure reproducing means for reading a file structureusing the read chaining information; an unallocated chaining informationarea address calculation and registration means for calculating andregistering in chaining information an address of an unallocatedchaining information area that is an unallocated area in an area wherechaining information is continuously recorded; a chaining informationrecording means for recording chaining information; an overrun extentrecording means for recording an overrun extent for preventing wrongaccess to an unrecorded area in a file structure and file reproducingoperation; and a close integrity information recording means forrecording close integrity information indicative of recordingcompletion.

The above noted object is achieved by a processing sequence such as thatof a data recording method for applying a opening process for beginningrecording data to a data storage medium in which a file managed using avolume/file structure is recorded and reproduced from one end of a datarecording area, and in which a number of data recording operations to asame area is limited, the data recording method characterized by avolume structure reproducing step for reading volume structure recordedin a formatting process; an integrity information reproducing step forreading the latest integrity information while reading in seriescompletely recorded close integrity information and open integrityinformation according to previously read volume structure content; achaining information reproducing step for reading the latest chaininginformation while reading in series completely recorded chaininginformation according to previously read volume structure content; anopen integrity information recording step for recording open integrityinformation; and an unallocated chaining information area addresscalculation and registration step for calculating and registering inchaining information an address of an unallocated chaining informationarea that is an unallocated area in an area where chaining informationis continuously recorded.

The above noted object is achieved by a processing means such as that ofa data recording apparatus for applying a closing process, forpreventing a performance drop resulting from wrong access to anunrecorded area, to a data storage medium in which a file managed usinga volume/file structure is recorded and reproduced from one end of adata recording area, and in which a number of data recording operationsto a same area is limited, the data recording apparatus characterized bya volume structure reproducing means for reading volume structurerecorded in a formatting process; an integrity information reproducingmeans for reading the latest integrity information while reading inseries completely recorded close integrity information and openintegrity information according to previously read volume structurecontent; a chaining information reproducing means for reading the latestchaining information while reading in series completely recordedchaining information according to previously read volume structurecontent; an open integrity information recording means for recordingopen integrity information; and an unallocated chaining information areaaddress calculation and registration means for calculating andregistering in chaining information an address of an unallocatedchaining information area that is an unallocated area in an area wherechaining information is continuously recorded.

The above noted object is achieved by a processing sequence such as thatof a data reproducing method for reproducing a file from a data storagemedium to which a volume/file structure is recorded by a formattingprocess and to which a number of data recording operations to a samearea is limited, the data reproducing method characterized by a volumestructure reproducing step for reading volume structure recorded in aformatting process; a chaining information reproducing step for readingthe latest chaining information while reading in series a plurality ofcontinuously recorded chaining information according to previously readvolume structure content; a file structure reproducing step for readingfile structure using the read chaining information; and a filereproducing step for retrieving and reading a file using the read filestructure.

The above noted object is achieved by a processing means such as that ofa data reproducing apparatus for reproducing a file from a data storagemedium to which a volume/file structure is recorded by a formattingprocess and to which a number of data recording operations to a samearea is limited, the data reproducing apparatus characterized by avolume structure reproducing means for reading volume structure recordedin a formatting process; a chaining information reproducing means forreading the latest chaining information while reading in series aplurality of continuously recorded chaining information according topreviously read volume structure content; a file structure reproducingmeans for reading file structure using the read chaining information;and a file reproducing means for retrieving and reading a file using theread file structure

Improvement Over the Prior Art

Chaining information storing management information for accessing anewly recorded data file and start address information for an unrecordeddata area in the volume space is recorded each time a file is written toa data storage medium according to the present invention. This makes itpossible to write data by file unit without accomplishing a finalizingprocess such as recording a lead-out area.

High speed access is also made possible by multiply recording chaininginformation to a plurality of contiguous areas so that the chaininginformation can be read in series from successively recorded areas.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a data structure diagram showing the area structure in a datastorage medium according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a data recording and reproducing apparatusaccording to a preferred embodiment of the present invention.

FIG. 3 is a flow chart describing a formatting process of a datarecording and reproducing apparatus according to the present invention.

FIG. 4 is a data structure diagram of a formatted data storage medium.

FIG. 5 is a flow chart describing a file recording process of a datarecording and reproducing apparatus according to the present invention.

FIG. 6 is a data structure diagram of a data storage medium after theclosing process is completed.

FIG. 7 is a flow chart describing a closing process of a data recordingand reproducing apparatus according to the present invention.

FIG. 8 is a data structure diagram of a data storage medium after theclosing process is completed.

FIG. 9 is a flow chart describing a opening process of a data recordingand reproducing apparatus according to the present invention.

FIG. 10 is a data structure diagram of a data storage medium after theopening process.

FIG. 11 is a flow chart of a file reproduction process in a datarecording and reproducing apparatus according to the present invention.

FIG. 12 is a block diagram of a read-only data reproducing apparatusaccording to the present invention.

FIG. 13 is a flow chart of a file reproduction process in a datareproducing apparatus according to the present invention.

FIG. 14 is a data structure diagram of a CD-R disc recorded with aconventional multi-session method.

FIG. 15 is a diagram of a directory structure for managing files ondisc.

FIG. 16 is a flow chart of a conventional multi-session data recordingoperation.

BEST MODE FOR CARRYING OUT THE INVENTION

With a data storage medium according to the present invention, chaininginformation storing the address of management information for retrievingthe latest file structure and a unrecorded disc area is recorded in thevolume space, and multiple chaining information are recordedcontinuously. It is therefore possible for operations for recording orreproducing new data files or file structure for managing data files toreproduce the latest file structure or retrieve an area for recordingnew data at high speed using this chaining information recorded multipleconsecutive times in the volume space.

A data storage medium according to the present invention also storesaddress information for unallocated chaining information areas that areunallocated and unrecorded parts of the recordable chaining informationarea where said chaining information is continuously sequentiallyrecorded. It is therefore possible for a disc recorder other than thedisc recorder that recorded a file to continue recording and reproducingfiles to the same disc.

The preferred embodiments of the present invention are described nextbelow with reference to the accompanying figures.

Embodiment 1

A data recording and reproducing apparatus for recording and reproducingfiles managed using a volume/file structure conforming to the ISO 13346standard using a data storage medium, such as a CD-R disc or CD-RW disc,in which the number of data recording operations to a same disc area islimited, and the data structure of this data storage medium, aredescribed below with reference to the accompanying figures as apreferred embodiment of the present invention.

FIG. 1 is a data structure diagram showing the area structure of a datastorage medium according to this preferred embodiment of the inventionwhen a root directory file file entry and unallocated space entry areused as part of the chaining information. As shown in FIG. 1, startingfrom volume structure area 101 to which the volume structure isrecorded, open integrity information area 103, volume structure area107, chaining information area 109, and file structure/file area 117 areformed in the volume space with link extents 102, 106, 108, and 116disposed therebetween.

To record data file (File-a) under the directory structure shown in FIG.15, a file structure/file containing data file (File-a) is firstrecorded to file structure/file area 119 sandwiching link extent 118.Next, chaining information area 111 is recorded sandwiching link extent110, completing one file recording operation.

When a data file (File-b) is then recorded according to the directorystructure shown in FIG. 15, file structure/file area 121 containing datafile (File-b) is recorded sandwiching link extent 120, and chaininginformation area 113 is recorded sandwiching link extent 112.

In the closing process accomplished so that this data structure will bereadable by a read-only disc drive without a unrecorded area detectioncapability, chaining information area 115 in chaining informationrecording area 11 is then recorded sandwiching link extent 114, andoverrun extent 122 is recorded with part left unrecorded. Finally, closeintegrity information area 105 is recorded sandwiching link extent 104.

In a opening process for again starting recording to a disc to which theclosing process has been applied, open integrity information area 123 isrecorded in the overrun extent.

To then record data file (File-c) under the directory structure shown inFIG. 15, file structure/file area 129 containing data file (File-c) isrecorded sandwiching link extent 128, and chaining information area 125is recorded.

It should be noted that while the outline of the data structure of adata storage medium shown in FIG. 1 has been described here, a moredetailed data structure will be further described below in conjunctionwith the data recording process.

It should be noted that the areas left unrecorded in the data structureresulting from the above-described process are: unrecorded area 124 towhich close integrity information is recorded; allocated chaininginformation area (unrecorded) 126 to which the next chaining informationis allocated by the chaining information recorded to chaininginformation area 125; unallocated chaining information area (unrecorded)127, which is reserved for chaining information but as yet unallocated;and unrecorded area 130.

FIG. 2 is a block diagram of a data recording and reproducing apparatusaccording to a preferred embodiment of the present invention. As shownin FIG. 2, this data recording and reproducing apparatus comprises asystem controller 201, memory circuit 202, I/O bus 203, magnetic discdrive 204, and optical disc drive 205.

The system controller 201, which is achieved with a control program anda microprocessor containing operating memory, comprises: volumestructure recording means 211 for recording volume structure; a volumestructure reproducing means 212 for reproducing the volume structure; afile structure recording means 213 for recording file structure; a filestructure reproducing means 214 for reproducing file structure; a filerecording means 215 for recording file data; a file reproducing means216 for reproducing file data; a integrity information recording means217 for recording integrity information; a integrity informationreproducing means 218 for reproducing integrity information; chaininginformation recording means 219 for recording chaining information;chaining information reproducing means 220 for reproducing chaininginformation; overrun extent recording means 221 for recording an overrunextent; and address calculation and registration means 222 forcalculating an address and registering location information as anallocation descriptor.

The memory circuit 202 comprises volume structure memory 231 used forcalculating and temporarily storing volume structure; file structurememory 232 used for calculating and temporarily storing file structureintegrity information memory 233 used for calculating and temporarilystoring integrity information; chaining information memory 234 used forcalculating and temporarily storing chaining information; and filememory 235 for temporarily storing a data file.

The formatting procedure for a data storage medium according to thepresent invention is described next below with reference to the blockdiagram in FIG. 2, the flow chart of the formatting process in FIG. 3,and a diagram of the data structure resulting from this formattingprocess shown in FIG. 4.

(S301) Following a control program stored internally as volume structurerecording means 211, the system controller 201 generates volumestructure containing a volume name and other predefined parameters inthe volume structure memory 231 of memory circuit 202. The systemcontroller 201 then instructs the optical disc drive 205 to record thevolume structure generated in volume structure memory 231 according tothis control program. The optical disc drive 205 internally generatesrecording data using this volume structure transferred from the volumestructure memory 231 that skips and leaves unrecorded the areas to whichopen integrity information and close integrity information are to berecorded, and has a predefined link block/run-in block and linkblock/run-out block added before and after the data to be recordedbefore the skip and after the skip, and records continuously from thelink block of link extent 106. When volume structure recording iscompleted, the optical disc drive 205 notifies the system controller 201that recording has ended.

It should be noted that the link block/run-in block added to the volumestructure before the skip is considered recorded outside the volumespace and not shown in the present embodiment.

(S302) Next, following a program stored internally as the integrityinformation recording means 217, the system controller 201 generatesopen integrity information in the integrity information memory 233 ofmemory circuit 202. Further following this control program, the systemcontroller 201 internally generates recording data having a predefinedlink block/run-in block and link block/run-out block added before andafter the open integrity information generated by the optical disc drive205 in the integrity information memory 233, and records continuouslyfrom the link block at the location of the specified recording startaddress.

This operation results in data being recorded twice to at least part ofthe link block because the above-noted volume structure recordingoperation and this open integrity information recording operationoverlap at the link block. This method of recording data bracketing alink area can be achieved using the control procedure as described abovewith reference to the related art.

When volume structure recording is completed, the optical disc drive 205notifies the system controller 201 that recording has ended.

(S303) Following a control program stored internally as addresscalculation and registration means 222, the system controller 201 nextcalculates the location of unrecorded area 418 and unallocated chaininginformation area (unrecorded area) 417 based on the number and length ofchaining information recorded to continuous areas matching the number offile recording operations, and registers this to chaining informationmemory 234 of memory circuit 202. Registers to part of chaininginformation. The detailed data structure of this registered addressinformation is further described below in conjunction with the chaininginformation. In this preferred embodiment of the invention, chaininginformation area 109 recorded during the formatting process, chaininginformation areas 111 and 113 recorded during file recording, andchaining information area 115 recorded during the closing process, arerecorded with link extents 110, 112, and 114 therebetween to acontiguous area that is reserved according to the number of filerecording operations for recording chaining information.

(S304) Following a control program stored internally as file structurerecording means 213, the system controller 201 next generates a rootdirectory file in file structure memory 232 of memory circuit 202. Then,following this control program, the system controller 201 instructs theoptical disc drive 205 to record the root directory file generated inthe file structure memory 232. In this recording operation command thesystem controller 201 specifies the start address of the recording areafor the root directory file, that is, the file structure.

As in the recording operation for the volume structure, the optical discdrive 205 internally generates recording data having a predefined linkblock/run-in block and run-out block/link block added before and afterthe root directory file transferred from the file structure memory 232,and records the recording data continuously from the link block at thespecified recording start address. When recording the root directoryfile is completed, the optical disc drive 205 notifies the systemcontroller 201 that recording has ended.

(S305) Following a control program stored internally as chaininginformation recording means 219, the system controller 201 generateschaining information in the chaining information memory 234 of memorycircuit 202. This chaining information has an information control block(ICB) structure according to the ISO 13346 standard, and in thispreferred embodiment of the invention comprises an ICB for managing aroot directory file, ICB for managing unallocated space, and paddingdata.

A root directory file ICB contains a file entry for managing a rootdirectory file, and an indirect entry with address information for afollowing file entry. The unallocated space ICB likewise comprises anunallocated space entry for managing unallocated space, and an indirectentry with address information for a following unallocated space entry.In addition to the address information of unrecorded area 419, theaddress information to unallocated chaining information area (unrecordedarea) 417 calculated in step (S303) is also registered in theunallocated space entry that is part of the chaining information. Thedetailed data structure of this chaining information is furtherdescribed below.

It should be noted that the address information to allocated chaininginformation area (unrecorded area) 416 is recorded to the indirect entry412 of the unallocated space entry of chaining information area 109, andthe indirect entry 414 of the file entry for the root directory.

It should be noted that the order of the chaining information is notspecifically limited. Furthermore, the padding data is dummy data forfilling the remaining part of an ECC block.

Moreover, the system controller 201 continues and instructs the opticaldisc drive 205 according to this control program to record the chaininginformation generated in chaining information memory 234.

The system controller 201 specifies the start address of the area forrecording the chaining information in this recording command withconsideration for the recording position of the previously recordedvolume structure area 107 and link extent 108. The optical disc drive205 internally generates recording data having a predefined linkblock/run-in block and link block/run-out block added before and afterthe chaining information transferred from the chaining informationmemory 234, and records the recording data continuously from the linkblock of link extent 108. When recording the chaining information iscompleted, the optical disc drive 205 notifies the system controller 201that recording has ended.

When the above-described formatting process is accomplished, a datastructure as shown in FIG. 4 is formed on the data storage medium. Itshould be noted that the arrows (S301) to (S305) added to FIG. 4indicate the area recorded in each step shown in FIG. 3.

It should be noted that the volume structure areas 101 and 107, openintegrity information area 103, chaining information area 109, and filestructure/file area 117 have been described in the above formattingprocess as being separately recorded in conformance to the command unitprocessing sequence of a computer system. However, if a dedicatedrecording device that is not dependent upon the architecture of acomputer system is used, it is also possible to format the disc bycontinuously recording volume structure areas 101 and 107, openintegrity information area 103, chaining information area 109, and filestructure/file area 117 while skipping the unrecorded areas. When asimplified formatting process such as this is accomplished, link extents102 and 108 shown in FIG. 4 are not present.

In addition, a primary volume descriptor 401 containing volume attributeinformation, partition descriptor 402 containing partition information,logical volume descriptor 403 containing information for identifyinglogical volumes, anchor volume descriptor 404 that becomes a anchorpoint for disc access, and file set descriptor 405 containing file setinformation and address information for the root directory file fileentry, are recorded as volume structure in the present embodiment. Itshould be noted that this volume structure shall not be limited to thisorder or type.

It should be noted that in ISO 13346 the file set descriptor is definedas part of the file structure, but in the data structure shown in FIG. 4after the formatting process according to this preferred embodiment, thefile set descriptor 405 is recorded in the volume structure area 101 aspart of the volume structure to simplify the description of operation.

A control procedure for a process for recording files to a data storagemedium as an embodiment of the present invention is described next withreference to the block diagram in FIG. 2, the data structure after theformatting process as shown in FIG. 4, the flow chart of this filerecording process shown in FIG. 5, and the diagram shown in FIG. 6 ofthe data structure after file recording. It should be noted that in thisfile recording process data file (File-a) and data file (File-b) storedto magnetic disc drive 204 are described below as being separatelyrecorded according to the directory structure shown in FIG. 15.

(S501) Following a control program stored internally as volume structurereproducing means 212, the system controller 201 instructs the opticaldisc drive 205 to read the volume structure recorded to an area having aspecific logical sector number. The optical disc drive 205 accesses thespecified area of the inserted disc (not shown in the figure), reads thevolume structure, and transfers the read volume structure to the volumestructure memory 231 of memory circuit 202. Next, the system controller201 interprets the content of the primary volume descriptor 401,partition descriptor 402, logical volume descriptor 403, and file setdescriptor 405 in order from the anchor volume descriptor 404 from inthe read volume structure, and obtains address information for thevolume information and logical volume integrity descriptor 406,unallocated space entry 411, that is, chaining information, and fileentry 413 for the root directory file.

In the present embodiment, address information for the root directoryfile file entry that is part of the chaining information recorded firstduring the formatting process is specified in the logical volumedescriptor 403, and address information for an unallocated space entryis specified in the partition descriptor 402. In addition, addressinformation for the logical volume integrity descriptor (open) 406, thatis, the first-recorded open integrity information, is specified by thelogical volume descriptor 403. It should be noted that the order of thechaining information shall not be specifically limited. It should benoted that in the present embodiment a volume structure area 107 isrecorded as a reserve volume structure area 101 so that when volumestructure area 101 cannot be reproduced, reproduction is possible fromvolume structure area 107.

(S502) Following a control program stored internally as chaininginformation reproducing means 220, system controller 201 commands a readoperation from the following chaining information area using the addressinformation obtained in step (S501) or step (S503) described below. Theoptical disc drive 205 accesses the specified chaining information areaand attempts data reproduction.

If data is reproduced from the specified chaining information area, theoptical disc drive 205 transfers the reproduced information to thechaining information memory 234 of memory circuit 202. At this timesystem controller 201 accomplishes step (S503) to retrieve the updatedchaining information area.

However, if data cannot be reproduced because the specified chaininginformation area is unrecorded, the system controller 201 determinesthat the last reproduced chaining information area is the latest, andproceeds from step (S504). For example, in a data storage medium havinga data structure as shown in FIG. 4 after the formatting process, theinformation read from chaining information area 109 is the latestchaining information, and unallocated space entry 411 contained thereinis used for managing unrecorded area 418 and unallocated chaininginformation area (unrecorded area) 417, while file entry (root) 413 isused for managing root directory file 150. Furthermore, in a datastorage medium having a data structure as shown in FIG. 6 after the filerecording process, the information read from chaining information area113 is the latest chaining information, and unallocated space entry 611contained therein is used for managing unrecorded area 622 while rootdirectory file file entry 613 is used for managing root directory file158. In other words, the address information for the unrecorded arearecorded to the latest unallocated space entry, and the addressinformation for the root directory file recorded in the file entry forthe latest root directory file, are obtained here.

It should be noted that the information recorded as the chaininginformation shall not be limited to the unallocated space entry and rootdirectory file file entry.

(S503) Following a control program stored internally as chaininginformation reproducing means 220, system controller 201 obtains addressinformation for each ICB recording area of the next chaining informationfrom the indirect entry of each ICB contained in the chaininginformation read in step (S502). In the present embodiment, addressinformation for the following unallocated space entry is obtained froman indirect entry of the unallocated space entry, and addressinformation for the next file entry is obtained from an indirect entryof the file entry (root). This indirect entry is described further indetail below.

(S504) Following a control program stored internally as file structurereproducing means 214, system controller 201 instructs the optical discdrive 205 to read the root directory file from the file structure/filearea using the address information for the root directory fileregistered in the file entry for the root directory file detected as thelatest chaining information in step (S502) or (S503). The optical discdrive 205 then accesses the file structure/file area and reads thelatest root directory file, and transfers it to the file structurememory 232 of memory circuit 202. For example, in a data storage mediumhaving a data structure as shown in FIG. 4 after the formatting process,root directory file 150 is transferred. In a data storage medium havinga data structure as shown in FIG. 6 after recording data file (File-a)and data file (File-b), root directory file 158 is transferred.

When this root directory file reproduction operation is completed, theoptical disc drive 205 notifies the system controller 201 that therecording operation has ended. It should be noted that when adding afile under a specific directory, subdirectories are sequentiallyaccessed from the root directory file in this step to read a specificdirectory file, directory files from the root directory file to aspecific directory are temporarily stored to file memory 235, and thefile entry that is the management information for these directories isstored to file structure memory 232.

(S505) Following a control program stored internally as file reproducingmeans 216, the system controller 201 reads data file (File-a) to berecorded to the data storage medium from magnetic disc drive 204, andtransfers it to file memory 235 of memory circuit 202. In addition, thesystem controller 201 generates a directory file (Dir-A) for managingdata file (File-a) according to the ISO 13346 standard. In addition,system controller 201 generates file entry (File-a) and file entry(Dir-A) for managing these files, and updates the content of the rootdirectory file read to file structure memory 232 in step (S504). Whenthe data to be recorded to file structure/file area 119 is thusgenerated, system controller 201 instructs the optical disc drive 205 torecord the file entry generated in file structure memory 232 and thedirectory file/data file generated in file memory 235 according to acontrol program stored internally as file structure recording means 213and file recording means 215.

The system controller 201 specifies the start address of the filestructure and file recording area 119 in this record command. Theaddress information specified here is obtained from the latestunallocated space entry detected in step (S502). The optical disc drive205 internally generates recording data having a predefined linkblock/run-in block and link block/run-out block added before and afterfile structure/file data comprising the file entry transferred from filestructure memory 232 and the directory file/data file transferred fromfile memory 235, and records continuously from the link block of linkextent 118.

When this file structure/file data recording operation ends, the opticaldisc drive 205 notifies the system controller 201 that recording iscompleted. When the above-described data recording operation iscompleted, data file (File-a) 151 and file entry 152 for managing it,file entry 153 for managing directory file (Dir-A), and root directory154 are formed in file structure/file area 119 as shown in FIG. 6. Itshould be noted that the directory file is not shown in the presentembodiment because directory file (Dir-A) is recorded embedded in thefile entry for managing the directory.

(S506) Following a control program stored internally as addresscalculation and registration means 222, the system controller 201 nextcalculates the address information of the unrecorded area at the mostoutside circumference and the location of the updated unallocatedchaining information area (unrecorded area), and registers this addressinformation as part of the chaining information in chaining informationmemory 234 of memory circuit 202. The unrecorded area at the mostoutside circumference is the area where the next file structure/file isrecorded, and when a next file is written the address information ofthis unallocated chaining information area (unrecorded area) isregistered in the indirect entry of the latest chaining information ICBas an allocated chaining information area.

(S507) Following a control program stored internally as chaininginformation recording means 219, the system controller 201 temporarilystores chaining information to chaining information memory 234. At thistime the address information for the root directory file temporarilystored in step (S505) and address information for the next chaininginformation, or address information for the next file structure/filearea calculated in step (S506) and address information for the updatedunallocated chaining information area (unrecorded area), are included inthe stored information. Next, the system controller 201 instructs theoptical disc drive 205 to record the chaining information generated inchaining information memory 234. In this recording operation command,the system controller 201 internally generates recording data having apredefined link block/run-in block and link block/run-out block addedbefore and after the chaining information from the address specified byindirect entry 411 for the unallocated space entry in the chaininginformation recorded in step (S305), and records continuously from linkextent 110.

(S508) To write a new data file (File-b), system controller 201 followsthe same control procedure as described in step (S505) to read the datafile (File-b) and file structure to be recorded to the data storagemedium from magnetic disc drive 204, and records to file structure/filearea 121. When this file recording operation ends, data file (File-b)155 and file entry 156 for managing it, file entry 157 for managingdirectory file (Dir-B), and root directory file 158, are formed in filestructure/file area 121.

(S509) Next, following the same control procedure as in step (S506),system controller 201 calculates address information for unrecorded area622 at the most outside circumference and address information for theupdated unallocated chaining information area (unrecorded area), andregisters it in chaining information memory 234 of memory circuit 202 aspart of the chaining information. Because the entire recordable area ofthe contiguous chaining information area reserved during the formattingprocess is already allocated in the present embodiment, there is noinformation to be registered as unallocated chaining information area.Therefore, the address information registered in chaining informationmemory 234 is only the address information for the unrecorded area 622at the most outside circumference.

(S510) Following the same control procedure as in step (S507), thesystem controller 201 temporarily stores chaining information in thechaining information memory 234. At this time address information forthe root directory file temporarily stored in step (S508) and addressinformation for the next chaining information, or the location of thenext file structure/file area calculated in step (S509), are stored withthis information, and recording data with a predefined link block/run-inblock and link block/run-out block added before and after the chaininginformation is internally generated from the address specified byindirect entry 602 of the unallocated space entry of the chaininginformation recorded in step (S507) and recorded continuously from linkextent 112.

When a file recording sequence as described above is accomplished, adata structure as shown in FIG. 6 is formed on the data storage medium.It should be noted that arrows (S507) to (S510) shown in FIG. 6 indicatethe areas recorded by the corresponding steps in FIG. 5.

It should be noted that while the data file, directory file, and fileentries for managing these are described as being recorded at once instep (S505) and step (S508), these can be individually recorded asindividual files and file entries. When these are individually recorded,a link block/run-in block and run-out block/link block are formed beforeand after each file or file entry. Furthermore, the recording positionsof any data file, directory file, and file entry for managing theserecorded in the file structure/file area are logically managed by thefile structure, and the recording sequence of the data file, directoryfile, and file entry for managing these shall not be limited to the thatshown in the data structure diagram in FIG. 6.

It should be noted that data reliability can be improved by re-readingrecorded data, including the file structure, after recording a file, andthen recording the file once again if the data cannot be reproduced.

It should be further noted that the file recording sequence for datafile (File-a) in step (S505), and the file recording sequence for datafile (File-b) in step (S508), can be performed on different recordingdevices.

It should be noted that in the present embodiment disc areas areallocated so that recording chaining information for two recordingoperations outside of the formatting process is possible, and chaininginformation for precisely two recording operations, that is, recordingdata file (File-a) and recording data file (File-b), is recorded.However, if it is desirable to write a further file before running theclosing process, the continuous recording area for chaining informationcan be allocated again using the chaining information used for theclosing process in the present invention. In this case, addressinformation for the latest root directory 158 is recorded in the fileentry of the root directory for the chaining information, and theaddress information immediately after the area that is re-reserved forcontinuously recording the chaining information, and the addressinformation of the unallocated chaining information area that isunallocated in the contiguous area reserved for chaining information arerecorded in unallocated space entry. It should be noted that reservingan area for contiguously recording chaining information according to thenumber of file recording operations can be accomplished once or pluraltimes.

A control procedure for a closing process for a data storage mediumaccording to the present invention is described next with reference tothe block diagram in FIG. 2, the diagram shown in FIG. 6 of the datastructure after the file recording process, the flow chart of thisclosing process shown in FIG. 7, and the diagram shown in FIG. 8 of thedata structure after the closing process.

(S701) As in step (S501) of the file recording operation describedabove, the system controller 201 interprets the volume structure readfrom volume structure area 101 or 107 to obtain the address informtionof the logical volume integrity descriptor recorded to open integrityinformation area 103, that is, the first integrity information, and theaddress information of the unallocated space entry and root directoryfile file entry recorded to chaining information area 109, that is, thefirst chaining information.

(S702) Following a control program stored internally as integrityinformation reproducing means 218, system controller 201 instructsreproducing the integrity information area using the address informationobtained in step (S701) or the following (S703). The optical disc drive205 accesses the specified integrity information area and attempts datareproduction. If data is reproduced from the specified integrityinformation area, the optical disc drive 205 transfers the reproducedintegrity information to the integrity information memory 233 of memorycircuit 202. The system controller 201 then performs step (S703) toretrieve the updated integrity information.

If data reproduction is not possible because the specified integrityinformation area is in an unrecorded state, the system controller 201performs step (S704) to retrieve the latest chaining information. Forexample, in a data storage medium having a data structure as shown inFIG. 6 after file recording, logical volume integrity descriptor (open)406 recorded to open integrity information area 103 is the latestintegrity information; in a data storage medium having a data structureas shown in FIG. 8 after the closing process, logical volume integritydescriptor (close) 801 recorded to close integrity information area 105is the latest integrity information. Integrity information is furtherdescribed below.

(S703) Following a control program stored internally as integrityinformation reproducing means 218, the system controller 201 obtains thelocation of the next integrity information area contained in theintegrity information read in step (S702).

(S704) As in step (S502) of the file recording operation describedabove, the system controller 201 tries to reproduce data from thechaining information area according to the address information obtainedin step (S701) or the following step (S705). If data is reproduced inthis step, step (S705) is performed to retrieve the updated chaininginformation.

If data reproduction is not possible because the area specified by theaddress information is not recorded, the system controller 201 decidesthat the last reproduced chaining information is the latest, andoperation continues from step (S706).

(S705) As in step (S503) of the above described file recordingoperation, the system controller 201 obtains the address of the nextchaining information area from the read chaining information.

(S706) As in step (S504) of the above described file recordingoperation, the system controller 201 references the latest chaininginformation read from the chaining information area, and reads the rootdirectory file file contained therein. For example, in FIG. 6, the datastructure after file recording, address information for the rootdirectory file is obtained from file entry 613 for the root directoryfile of the latest chaining information area 113, and root directoryfile 158 is reproduced. Next, starting from this root directory file158, system controller 201 sequentially reads and references the contentof file entry 153 for directory file (Dir-A), directory file (Dir-A)contained in this file entry, and file entry 152 for data file (File-a).

(S707) Following a control program stored internally as addresscalculation and registration means 222, the system controller 201calculates the address information of the next unrecorded area at themost outside circumference using the address information obtained instep (S705), and registers this address information in chaininginformation memory 234. It should be noted that in the presentembodiment, to enable the number of file recording operations to bespecified in the opening process sequence described further below, theunallocated chaining information area (unrecorded area) is notcalculated and registered in this calculation. It should be noted thatthe unallocated chaining information area (unrecorded area) can becalculated and registered in the closing process sequence. In this case,a contiguous area is reserved for the chaining information from theunrecorded area after the closing process, and the unallocated part ofthe area is temporarily stored in the chaining information memory 234 ofmemory circuit 202 as the unallocated chaining information area. Itshould be noted, however, that the number of file recording operationsis simply not specified in the opening process, and this has no affecton the file recording and reproducing process.

(S708) Following the same control program as in step (S507) and (S510),the system controller 201 temporarily stores chaining information to thechaining information memory 234. The address information for the rootdirectory file read in step (S706), and address information for the nextchaining information, are stored with this information at this time,recording data having a predefined link block/run-in block and linkblock/run-out block added before and after the chaining information isinternally generated from the address specified by indirect entry 612for the unallocated space entry of the chaining information recorded instep (S510), and recorded continuously from link extent 114.

(S709) Following a control program stored internally as overrun extentrecording means 221, system controller 201 instructs the optical discdrive 205 to record the overrun extent. Overrun extent 122 is comprisedby recording a plurality of overrun blocks. An overrun extent is formedby the optical disc drive 205 plurally recording, with consideration forthe recording size of open integrity information area 821 and closeintegrity information area 822, an area comprising a run-outblock/overrun block/link block/run-in block before and after eachoverrun block. An overrun extent is thus formed by recording an overrunblock to an area located before and after an unrecorded area allocatedfor updating chaining information, close integrity information, and openintegrity information. When the overrun extent recording operation ends,the optical disc drive 205 notifies the system controller 201 that therecording operation is completed.

(S710) Following a control program stored internally as integrityinformation recording means 217, system controller 201 temporarilystores close integrity information to the integrity information memory233. Next, system controller 201 instructs the optical disc drive 205 torecord the close integrity information stored in integrity informationmemory 233. In this recording operation command, system controller 201internally generates, from the address of the next integrity informationarea specified by the latest integrity information obtained in step(S703), recording data by adding a predefined link block/run-in blockand link block/run-out block before and after the close integrityinformation, and records logical volume integrity descriptor (close) 801to close integrity information area 105.

When the closing process described above is performed, a data structureas shown in FIG. 8 is formed on the data storage medium. It should benoted that arrows (S708) to (S710) shown in FIG. 8 indicate the areasrecorded by the corresponding steps in FIG. 7.

It should be noted that in the present embodiment a continuous area isreserved so that recording chaining information for two recordingoperations outside of the formatting process is possible, and chaininginformation for precisely two recording operations, that is, recordingdata file (File-a) and recording data file (File-b), is recorded.However, if only one file has been recorded when the closing process isaccomplished, file reproduction is made possible in the presentinvention by recording padding data, that is, dummy data (such as 00h)filling the area for chaining information that is not needed for theclosing process.

The open integrity information and close integrity information used asintegrity information are described next below. Open integrityinformation is recorded at the start of data recording, and indicatesthat a file can be recorded. Close integrity information is recordedwhen data recording is completed, and indicates that there is a matchassured between the recorded file and the file management information.This integrity information assures a data match in the recording device,while at the same time providing a means whereby a read-only reproducingdevice without the ability to detect a disc location in an unrecordedarea can determine whether all of the recorded data is reproducible, orwhether data that cannot be reproduced has been further recorded sincethe closing process was performed.

It should be noted that considering the possibility for read errors, thelogical volume integrity descriptor recorded to the integrityinformation area can be plurally recorded across more than one ECCblock. It should be further noted that this closing process is performedwhen the latest integrity information is open integrity information, andit is not necessary to perform another closing process when the latestintegrity information is close integrity information.

Furthermore, the overrun extent recorded in step (S709) is an area that,similarly to the lead-out area described in the prior art, is recordedto prevent an overrun into unrecorded area 131 when a read-only discreproducing device without the ability to detect an address from an areawhere no data is recorded accesses area 124, which is not recorded. Inaddition, because unrecorded area 124 is an area of approximatelyseveral tracks with recorded areas provided therefore and thereafter,misoperation resulting from servo errors can be prevented even if aread-only disc reproducing device accesses these areas.

A control procedure for a opening process to start recording to a datastorage medium according to a preferred embodiment of the presentinvention is described next with reference to the block diagram in FIG.2, the data structure diagram shown in FIG. 8 after the closing process,the flow chart of this opening process shown in FIG. 9, and the datastructure diagram shown in FIG. 10 after this opening process.

(S901) As in step (S501) of the above described file recordingoperation, the system controller 201 interprets the volume structureread from the volume structure area 101 or 107, and obtains the addressinformation of the logical volume integrity descriptor recorded to openintegrity information area 103, that is, the first integrityinformation, and the address information of the file entry for theunallocated space entry and root directory file recorded to chaininginformation area 109, that is, the first chaining information.

(S902) Next, as in step (S702) of the above described closing process,the system controller 201 instructs that the integrity information areabe reproduced using the address information obtained from step (S901) orthe following step (S903) following a program stored internally asintegrity information reproducing means 218. The optical disc drive 205then accesses the specified integrity information area and tries toreproduce data. If data is reproduced from the specified integrityinformation area, the optical disc drive 205 transfers the reproducedintegrity information to the integrity information memory 233 of memorycircuit 202. The system controller 201 then performs step (S903) toretrieve the updated integrity information.

If data reproduction is not possible because the specified integrityinformation area is unrecorded, the system controller 201 performs step(S904) to retrieve the latest chaining information.

(S903) As in step (S703) of the above-described closing process, thesystem controller 201 obtains the address information of the nextintegrity information area contained in the integrity information readin step (S902) following a control program stored internally asintegrity information reproducing means 218.

(S904) As in step (S502) of the above-described file recordingoperation, the system controller 201 attempts data reproduction from thechaining information area according to the address information obtainedin step (S901) or the following (S905). If data is reproduced in thisstep, step (S905) is performed to retrieve the updated chaininginformation. However, if data reproduction is not possible because thearea specified by this address information is unrecorded, systemcontroller 201 determines that the last reproduced chaining informationis the latest, and continues from step (S906).

(S905) As in step (S503) of the above-described file recordingoperation, the system controller 201 retrieves the address informationof the next chaining information area from the read chaininginformation.

(S906) Following a control program stored internally as integrityinformation recording means 217, system controller 201 temporarilystores the open integrity information to integrity information memory233. Next, the system controller 201 instructs the optical disc drive205 to record the open integrity information generated in integrityinformation memory 233. In this recording operation command, systemcontroller 201 internally generates, from the address of the nextintegrity information specified by the latest integrity informationobtained in step (S903), recording data having a predefined linkblock/run-in block and link block/run-out block added before and afterthe open integrity information, and records a logical volume integritydescriptor (open) to the open integrity information area 123.

(S907) Following a control program stored internally as addresscalculation and registration means 222, system controller 201, using theaddress information obtained in step (S905), calculates the location ofunrecorded area 1004 and unallocated chaining information area(unrecorded area) 1003 from the number and length of chaininginformation recorded to a continuous area matching the number of filerecording operations, and registers this as part of the chaininginformation. The next possible recording start address information iscalculated, and temporarily stored to chaining information memory 234 ofmemory circuit 202. It should be noted that address informationcalculated in this step is not registered in the allocation descriptorof the unallocated space entry. The next time a file is recorded, thisaddress information is recalculated, and recorded as the unallocatedspace entry part of the chaining information.

When another new data file (File-c) is written under the directorystructure shown in FIG. 15 using the same file recording operationdescribed with reference to FIG. 5 to a data storage medium having adata structure as described above and shown in FIG. 10, a data structureas shown in FIG. 1 is formed on the data storage medium.

The detailed data structure of the chaining information, and moreparticularly the address information for unrecorded areas managed by theunallocated space entry of the chaining information, are described nextin detail. The address information recorded in the chaining informationis calculated in step (S303) of the formatting process shown in FIG. 3,steps (S506) and (S509) of the file recording operation process shown inFIG. 5, step (S708) of the closing process shown in FIG. 7, or step(S908) of the opening process shown in FIG. 9. In this embodiment of theinvention, this calculated address information is recorded as anallocation descriptor of an unallocated space entry that is part of thechaining information. The chaining information is recorded in step(S305) of the formatting process shown in FIG. 3, steps (S507) and(S510) of the file recording operation process shown in FIG. 5, or step(S709) of the closing process shown in FIG. 7. As described withreference to step (S305), this chaining information has an ICB structureusing ICB strategy 4096 defined as an implementation of ISO 13346, andcomprises in this preferred embodiment of the invention an ICB formanaging the root directory file, an ICB for managing unallocated space,and padding data.

Descriptor tag 181 for identifying the descriptor as an unallocatedspace entry, allocation descriptor 182 for managing unallocated chaininginformation area addresses, and allocation descriptor 183 for managingunrecorded area address information, are recorded to the unallocatedspace entry 171 of the unallocated space ICB. In addition, descriptortag 184 for identifying the descriptor as an indirect entry, and addressinformation 185 for the next recorded unallocated space entry, arerecorded to the indirect entry 172 of this unallocated space ICB. Inaddition, descriptor tag 186 for identifying a descriptor as a fileentry, and allocation tag 187 for storing the address information of theroot directory file, are recorded to file entry (root) 173 of the rootdirectory file ICB. Descriptor tag 188 for identifying a descriptor asan indirect entry, and address information 189 for the file entry (root)recorded next, are recorded to the indirect entry 174 of this rootdirectory file ICB. Because the chaining information records the addressinformation of the next ICB recorded in the indirect entry of theseICBs, successive chaining information can be accessed in series. When itis detected that data is not recorded at the last specified address, itis determined that chaining information should be recorded next to thatarea, and that the last recorded latest chaining information is the oneprevious chaining information.

In this preferred embodiment of the invention, address informationrecorded to the allocation descriptor of the latest unallocated spaceentry is simultaneously the file structure/file recording start addressinformation and the address information of the area reserved forchaining information, and the address information of the root directoryrecorded to the allocation descriptor of the file entry for the latestroot directory file simultaneously indicates that file reproduction ispossible from the latest file management information. When the datastorage medium uses a physical format in which data is recorded in ECCblock units with error correction code added for a plurality of sectors,padding data 156 is recorded to the data storage medium after formingECC blocks by adding padding data to valid data.

Address information for unrecorded areas that are managed by theunallocated space entry that is one characteristic of the presentinvention is described next. Allocation descriptor 182 for managing theunallocated chaining information area address information, andallocation descriptor 183 for managing unrecorded area addressinformation, that are recorded to the unallocated space entry areaddress information for unallocated areas that are both unrecorded andnot specified from any information; in the future, chaining informationwill be recorded to the unallocated chaining information area managed byallocation descriptor 182, and a file structure/file or overrun extentwill be recorded to the unrecorded area managed by allocation descriptor183. It should be noted that the allocation descriptors recorded to theunallocated space entry shall not be limited to these two types.

An area to which continuous chaining information matching the number offile write operations can be recorded is assured in the formattingprocess and opening process of the present invention. This area isbroadly categorized as one of three areas: an area to which chaininginformation is recorded, an allocated chaining information area that isalready allocated for recording the next chaining information by theindirect entry that is the previous chaining information ICB, or anunallocated chaining information area that is both unallocated andunrecorded and is neither of the above two areas. The addressinformation of this unallocated chaining information area is recorded inthe allocation descriptor of the unallocated space entry in previouschaining information. For example, in the data structure diagram afterthe formatting process shown in FIG. 4, address information for theallocation descriptor of unrecorded area 418 and unallocated chaininginformation area (unrecorded area) 417 is recorded in unallocated spaceentry 411. Furthermore, the address information for this unrecorded areaand the unallocated chaining information area is recalculated in thefile recording sequence and closing process, and the updated informationis registered in the chaining information as an allocation descriptor.It should be noted that these calculations must consider the size of alink extent that may be present.

The control sequence of a file reproducing process applied by a datarecording and reproducing apparatus to a data storage medium accordingto the present invention is described next below with reference to theblock diagram in FIG. 2, the flow chart in FIG. 11 of the filereproducing process, and the data structure diagram shown in FIG. 1. Itshould be noted that data file (File-a) managed using the directorystructure shown in FIG. 15 is reproduced in this file recording process.

(S1101) As in step (S501) of the above described file recordingoperation, the system controller 201 interprets the volume structureread from the volume structure area 101 or 107, and obtains the addressinformation of the logical volume integrity descriptor recorded to openintegrity information area 103, that is, the first integrityinformation, and the address information of the file entry for theunallocated space entry and root directory file recorded to chaininginformation area 109, that is, the first chaining information.

(S1102) As in step (S502) of the file recording operation describedabove, following a control program stored internally as chaininginformation reproducing means 220, the system controller 201 tries toreproduce data from each chaining information area recorded to acontinuous area using the address information obtained in step (S501) orthe following step (S503). If data is reproduced from the specifiedchaining information area, step (S1103) is performed to search theupdated chaining information area.

If data reproduction is not possible because the specified chaininginformation area is not recorded, the system controller 201 decides thatthe last reproduced chaining information is the latest, and operationcontinues from step (S1104).

(S1103) As in step (S503) of the above described file recordingoperation, the system controller 201 obtains the address information ofthe next chaining information area from the read chaining information.

(S1104) As in step (S504) of the above described file recordingoperation, the system controller 201 references the latest chaininginformation read from chaining information area 125, and reads rootdirectory file 162 according to the allocation descriptor 187 of thefile entry 173 for the root directory file. Next, starting at this rootdirectory file 162, system controller 201 sequentially reads andreferences the content of file entry 153 of directory file (Dir-A) anddirectory file (Dir-A) recorded in this file entry, and file entry 152of data file (File-a).

(S1105) Finally, system controller 201 reads file (File-a) 151 by meansof file reproducing means 216, and completes the file reproducingoperation.

A file reproduction process whereby a data reproducing apparatus readsfiles from a data storage medium according to the present invention isdescribed next below with reference to the block diagram in FIG. 12, theflow chart of a file reproducing process shown in FIG. 13, and the datastructure diagram shown in FIG. 1. It should be noted that a data file(File-a) managed using the directory structure shown in FIG. 15 isreproduced in this file recording process.

FIG. 12 is a block diagram of a data reproducing apparatus according toa preferred embodiment of the present invention. As shown in FIG. 12,this data reproducing apparatus comprises a system controller 1201,memory circuit 1202, I/O bus 1203, and optical disc drive 1204.

The system controller 1201, which is achieved with a control program anda microprocessor containing operating memory, comprises: volumestructure reproducing means 1211 for reproducing volume structure; afile structure reproducing means 1212 for reproducing file structure; afile reproducing means 1213 for reproducing file data; a integrityinformation reproducing means 1214 for reproducing integrityinformation; and chaining information reproducing means 1215 forreproducing chaining information.

The memory circuit 1202 comprises volume structure memory 1221 used forcalculating and temporarily storing volume structure; file structurememory 1222 used for calculating and temporarily storing file structureintegrity information memory 1223 used for calculating and temporarilystoring integrity information; chaining information memory 1224 used forcalculating and temporarily storing chaining information; and filememory 1225 for temporarily storing a data file.

(S1301) As in step (S501) of the above described file recordingoperation, the system controller 1201 interprets the volume structureread from the volume structure area 101 or 107, and obtains the addressinformation of the logical volume integrity descriptor recorded to openintegrity information area 103, that is, the first integrityinformation, and the address information of the file entry for theunallocated space entry and root directory file recorded to chaininginformation area 109, that is, the first chaining information.

(S1302) As in step (S702) of the above described file recordingoperation, the system controller 1201 attempts data reproduction fromthe integrity information area according to the address informationobtained from step (S1301) or the following step (S1303). If data isreproduced in this step, step (S1303) is performed to retrieve theupdated integrity information. However, is data reproduction is notpossible because the area specified by this address information is notrecorded, system controller 1201 determines that the last reproducedintegrity information is the latest, and proceeds from step (S1304). Asnoted above, each integrity information stores the address informationof the next integrity information, and that address specifies the areato which integrity information is to be recorded next. If the area readfrom an integrity information as the area to which the next integrityinformation should be recorded is unrecorded, it is possible todetermine that that integrity information is the latest.

It should be noted that if the integrity information determined as thelatest is open integrity information, it is known that data recording isincomplete because of, for example, the disc being removed whilerecording was in progress; if close integrity information, a data matchis verified because it is known that data recording has been completedto the current point. In this step, the disc reproducing device will notmalfunction even if unrecorded area 124 for close integrity informationin the overrun extent is accessed because a recorded area containingdummy data is located therebefore and thereafter. In this exemplaryembodiment the latest integrity information is open integrityinformation. Open integrity information means that data recordingstopped before recording was completed because the disc was ejected oran error occurred during recording, for example.

In a read-only disc player, a disc is read by treating the data recordedthrough the close integrity information preceding this open integrityinformation as valid data. In a disc recorder, a search utility can beused to find the end of the recorded data and thereby enable datarecovery.

It should be noted that the area beyond the overrun extent where closeintegrity information is not recorded need not be accessed because theoverrun extent to which the last file entry (root) is recorded can bedetermined by detecting the last close integrity information. It istherefore possible to efficiently detect the last file entry (root)because the location of the last overrun extent is already known whenlooking for the last file entry (root).

(S1303) As in step (S703) of the above described closing process, thesystem controller 1201 obtains the address information of the nextintegrity information area from the read integrity information.

(S1304) As in step (S502) of the above described file recordingoperation, system controller 1201 attempts to read data from eachchaining information area recorded to a continuous area according to theaddress information obtained in step (S1301) or the following step(S1305). If data is reproduced in this step, step (S1305) is performedto retrieve the updated chaining information. However, if datareproduction is not possible because the area specified by this addressinformation is unrecorded, system controller 1201 determines the lastreproduced chaining information to be the latest, and proceeds from step(S1306).

(S1305) As in step (S503) of the above described file recordingoperation, system controller 1201 obtains the address information of thenext chaining information area from the read chaining information.

(S1306) As in step (S1306) of the above described file recordingoperation, system controller 1201 references the latest chaininginformation read from chaining information area 115, and reads rootdirectory file 158 according to the allocation descriptor of file entry813 for the root directory file contained therein. Next, starting fromthis root directory file 158, system controller 1201 sequentially readsand references the content of directory file (Dir-A) file entry 153 andthe directory file (Dir-A) recorded in this file entry, and data file(File-a) file entry 152.

(S1307) Finally, system controller 1201 reads data file (File-a) 141 bymeans of file reproducing means 1216, and completes the file reproducingoperation.

The search operation of the latest chaining information carried out inthe reproducing operation in the disc recording or disc reproducingapparatus is being done by repeating the sequence operation of obtainingand reading, from the volume structure, the address information of thechaining information which appears after the first recorded chaininginformation. Since the pieces of chaining information, which are to beread out in the chain, are stored in areas sequentially continued, thedriver unit may need not to seek the head for access purpose, but ableto read a plurality of pieces of chaining information recorded in thatareas, resulting in fast access. Also, the search operation of thelatest chaining information may be done not only during the filereproducing operation, but also during the file recording operation.

It should be noted that a file structure that is accessible from thelast file entry is assured of having a structure that is a complete filestructure. It will therefore be obvious that on a specific read-onlydisc drive a specific file can be read by retrieving only the file entrywithout retrieving integrity information.

It should be noted that an overrun extent is an area added before andafter a unrecorded area where dummy data is accessed so that servoerrors do not occur if the drive accesses a unrecorded disc area, andthe overrun extent only needs to be large enough to achieve thisobjective.

It should be noted that when an area that should be recorded in anoverrun extent is determined to be unrecorded, the immediately precedingchaining information and integrity information is determined to be thelatest, but this shall not be limited to detection of an unrecordedarea. It will be obvious that the above described file recordingoperation is performed in the same way for data file (File-b) and datafile (File-c). It is possible with this type of file reproducingoperation to retrieve and reproduce all data files using only the volumestructure and file structure recorded in the volume space. A specialcommand for reading TOC data, which is a type of file retrievalinformation, from the lead-in area as described in the prior art istherefore not necessary, and all files can be reproduced using only theREAD command used for data reproduction operations in the volume space.

It should be noted that compatibility with existing file systems is highbecause reading is possible using the file system of conventionalread-only disc drives once the latest root directory file is found.

It is thus possible to reproduce the volume/file structure and filesusing only data in the volume space by thus using chaining informationto manage file and file structure update information and specify thenext possible recording start address. It is therefore not necessaryread from a physical area using a special command, and recording andreproducing operations can be accomplished using only normal READ andWRITE commands.

Furthermore, recording open and close integrity information makes itpossible to assure data match integrity and to recover data in the eventan error occurs during recording.

Furthermore, recording the above noted chaining information andintegrity information in an overrun extent enables the latest chaininginformation and integrity information to be retrieved while at the sametime enabling the recording start position for new data to be detectedwithout entering an unrecorded area.

Furthermore, sequentially recording this chaining information to acontiguous area enables high speed access by reading this chaininginformation in series.

Furthermore, recording compatibility between disc recorders can beachieved by recording address information for the unallocated andunrecorded part of this contiguous chaining information area.

What is claimed is:
 1. A data storage medium in which a file managedusing a volume/file structure is recorded and reproduced from one end ofa data recording area, and in which a number of data recordingoperations to a same area is limited, comprising: an area forcontinuously recording a plurality of chaining information areas towhich is recorded chaining information containing root directory filemanagement information having location information for a next rootdirectory file allocated for update recording, and unallocated areamanagement information having location information for a next unrecordedarea.
 2. A data storage medium as described in claim 1, wherein saidarea for continuously recording a plurality of said chaining informationareas is located immediately following an overrun extent first recordedfor recording an overrun block for preventing a performance drop as aresult of wrong access to an unrecorded area.
 3. A data storage mediumas described in claim 1, wherein said chaining information storesaddress information for an unallocated chaining information area thathas not been allocated in the area where a chaining information area iscontinuously recorded.
 4. A data storage medium as described in claim 3,wherein said unallocated chaining information area address informationis recorded as an allocation descriptor of an unallocated space entrythat is part of the chaining information.
 5. A data recording method forapplying a formatting process to a data storage medium in which a filemanaged using a volume/file structure is recorded and reproduced fromone end of a data recording area, and in which a number of datarecording operations to a same area is limited, comprising: a volumestructure recording step for recording volume structure; an openintegrity information recording step for recording open integrityinformation indicating a formatting process start status; an unallocatedchaining information area address calculation and registration step forcalculating and registering in chaining information an address of anunallocated chaining information area that is an unallocated area in anarea where chaining information is continuously recorded; a rootdirectory file recording step for recording a root directory file; and achaining information recording step for recording chaining information.6. A data recording method as described in claim 5, wherein in theunallocated chaining information area address calculation andregistration step the unallocated chaining information area addressinformation is registered as an allocation descriptor for an unallocatedspace entry of the chaining information.
 7. A data recording apparatusfor applying a formatting process to a data storage medium in which afile managed using a volume/file structure is recorded and reproducedfrom one end of a data recording area, and in which a number of datarecording operations to a same area is limited, comprising: a volumestructure recording means for recording volume structure; an openintegrity information recording means for recording open integrityinformation indicating a formatting process start status; an addresscalculation and registration means for calculating and registering inchaining information an address of an unallocated chaining informationarea that is an unallocated area in an area where chaining informationis continuously recorded; a file structure recording means for recordinga root directory file; and a chaining information recording means forrecording chaining information.
 8. The data recording apparatus asdescribed in claim 7, wherein in the unallocated chaining informationarea address calculation and registration means the unallocated chaininginformation area address information is registered as an allocationdescriptor for an unallocated space entry of the chaining information.9. A data recording method for recording a file to a data storage mediumin which a file managed using a volume/file structure is recorded andreproduced from one end of a data recording area, and in which a numberof data recording operations to a same area is limited, comprising: avolume structure reproducing step for reading volume structure recordedin a formatting process; a chaining information reproducing step forreading the latest chaining information while reading in seriescompletely recorded chaining information according to previously readvolume structure content; a file structure reproducing step for readinga file structure; a file recording step for accomplishing data filerecording; a file structure recording step for accomplishing filestructure recording; an address calculation and registration step forcalculating and registering in chaining information an addressinformation of an unallocated chaining information area that is anunallocated area in an area where a plurality of chaining information iscontinuously recorded; and a chaining information recording step forrecording chaining information.
 10. A data recording method as describedin claim 9, wherein in the unallocated chaining information area addresscalculation and registration step the unallocated chaining informationarea address information is registered as an allocation descriptor foran unallocated space entry of the chaining information.
 11. A datarecording method as described in claim 9, wherein when the area wherechaining information is continuously recorded is insufficient for anumber of file write operations, the unallocated chaining informationarea address calculation and registration step calculates andre-reserves an address of an area where chaining information iscontinuously recorded.
 12. A data recording apparatus for recording afile to a data storage medium in which a file managed using avolume/file structure is recorded and reproduced from one end of a datarecording area, and in which a number of data recording operations to asame area is limited, comprising: a volume structure reproducing meansfor reading volume structure recorded in a formatting process; achaining information reproducing means for reading the latest chaininginformation while reading in series completely recorded chaininginformation according to previously read volume structure content; afile structure reproducing means for reading a file structure; a filerecording means for accomplishing data file recording; a file structurerecording means for accomplishing file structure recording; an addresscalculation and registration means for calculating and registering inchaining information an address infornmation of an unallocated chaininginformation area that is an unallocated area in an area where aplurality of chaining information is continuously recorded; and achaining information recording for recording chaining information.
 13. Adata recording apparatus as described in claim 12, wherein in theunallocated chaining information area address calculation andregistration means the unallocated chaining information area addressinformation is registered as an allocation descriptor for an unallocatedspace entry of the chaining information.
 14. A data recording apparatusas described in claim 13, wherein when the area where chaininginformation is continuously recorded is insufficient for a number offile write operations, the unallocated chaining information area addresscalculation and registration means calculates and re-reserves an addressof an area where chaining information is continuously recorded.
 15. Adata recording method for applying a closing process, for preventing aperformance drop resulting from wrong access to an unrecorded area, to adata storage medium in which a file managed using a volume/filestructure is recorded and reproduced from one end of a data recordingarea, and in which a number of data recording operations to a same areais limited, comprising: a volume structure reproducing step for readingvolume structure recorded in a formatting process; an integrityinformation reproducing step for reading the latest integrityinformation while reading in series completely recorded close integrityinformation and open integrity information according to previously readvolume structure content; a chaining information reproducing step forreading the latest chaining information while reading in seriescompletely recorded chaining information according to previously readvolume structure content; a file structure reproducing step for readinga file structure using the read chaining information; an unallocatedchaining information area address calculation and registration step forcalculating and registering in chaining information an address of anunallocated chaining information area that is an unallocated area in anarea where chaining information is continuously recorded; a chaininginformation recording step for recording chaining information; anoverrun extent recording step for recording an overrun extent forpreventing wrong access to an unrecorded area in a file structure andfile reproducing operation; and a close integrity information recordingstep for recording close integrity information indicative of recordingcompletion.
 16. A data recording method as described in claim 15,wherein the chaining information recording step is characterized byrecording with padding data, which is dummy data filling an unrecordedarea of the area in which chaining information is continuously recorded.17. A data recording method as described in claim 15, wherein theunallocated chaining information area address calculation andregistration step calculates and records in chaining information addressinformation of an area where chaining information recorded at a nextfile recording is continuously recorded.
 18. A data recording apparatusfor applying a closing process, for preventing a performance dropresulting from wrong access to an unrecorded area, to a data storagemedium in which a file managed using a volume/file structure is recordedand reproduced from one end of a data recording area, and in which anumber of data recording operations to a same area is limited,comprising: a volume structure reproducing means for reading volumestructure recorded in a formatting process; an integrity informationreproducing means for reading the latest integrity information whilereading in series completely recorded close integrity information andopen integrity information according to previously read volume structurecontent; a chaining information reproducing means for reading the latestchaining information while reading in series completely recordedchaining information according to previously read volume structurecontent; a file structure reproducing means for reading a file structureusing the read chaining information; an unallocated chaining informationarea address calculation and registration means for calculating andregistering in chaining information an address of an unallocatedchaining information area that is an unallocated area in an area wherechaining information is continuously recorded; a chaining informationrecording means for recording chaining information; an overrun extentrecording means for recording an overrun extent for preventing wrongaccess to an unrecorded area in a file structure and file reproducingoperation; and a close integrity information recording means forrecording close integrity information indicative of recordingcompletion.
 19. A data recording apparatus as described in claim 18,wherein unallocated chaining information area address calculation andregistration means calculates and records in chaining informationaddress information of an area where chaining information recorded at anext file recording is continuously recorded.
 20. A data recordingapparatus as described in claim 18, wherein the chaining informationrecording means is characterized by recording with padding data, whichis dummy data filling an unrecorded area of the area in which chaininginformation is continuously recorded.
 21. A data recording method forapplying a opening process for beginning recording data to a datastorage medium in which a file managed using a volume/file structure isrecorded and reproduced from one end of a data recording area, and inwhich a number of data recording operations to a same area is limited,comprising: a volume structure reproducing step for reading volumestructure recorded in a formatting process; an integrity informationreproducing step for reading the latest integrity information whilereading in series completely recorded close integrity information andopen integrity information according to previously read volume structurecontent; a chaining information reproducing step for reading the latestchaining information while reading in series completely recordedchaining information according to previously read volume structurecontent; an open integrity information recording step for recording openintegrity information; and an unallocated chaining information areaaddress calculation and registration step for calculating andregistering in chaining information an address of an unallocatedchaining information area that is an unallocated area in an area wherechaining information is continuously recorded.
 22. A data recordingmethod as described in claim 21, wherein the address informationcalculated in the unallocated chaining information area addresscalculation and registration step is an allocation descriptor for anunallocated space entry of the chaining information.
 23. A datarecording apparatus for applying a closing process, for preventing aperformance drop resulting from wrong access to an unrecorded area, to adata storage medium in which a file managed using a volume/filestructure is recorded and reproduced from one end of a data recordingarea, and in which a number of data recording operations to a same areais limited, comprising: a volume structure reproducing means for readingvolume structure recorded in a formatting process; an integrityinformation reproducing means for reading the latest integrityinformation while reading in series completely recorded close integrityinformation and open integrity information according to previously readvolume structure content; a chaining information reproducing means forreading the latest chaining information while reading in seriescompletely recorded chaining information according to previously readvolume structure content; an open integrity information recording meansfor recording open integrity information; and an unallocated chaininginformation area address calculation and registration means forcalculating and registering in chaining information an address of anunallocated chaining information area that is an unallocated area in anarea where chaining information is continuously recorded.
 24. A datarecording apparatus as described in claim 23, wherein the addressinformation calculated in the unallocated chaining information areaaddress calculation and registration means is an allocation descriptorfor an unallocated space entry of the chaining information.
 25. A datareproducing method for reproducing a file from a data storage medium towhich a volume/file structure is recorded by a formatting process and towhich a number of data recording operations to a same area is limited,comprising: a volume structure reproducing step for reading volumestructure recorded in a formatting process; a chaining informationreproducing step for reading the latest chaining information whilereading in series a plurality of continuously recorded chaininginformation according to previously read volume structure content; afile structure reproducing step for reading file structure using theread chaining information; and a file reproducing step for retrievingand reading a file using the read file structure.
 26. A data reproducingmethod as described in claim 25, further comprising an integrityinformation reproducing step for reading the latest close integrityinformation while reading in series close integrity information and openintegrity information according to previously read volume structurecontent.
 27. A data reproducing apparatus for reproducing a file from adata storage medium to which a volume/file structure is recorded by aformatting process and to which a number of data recording operations toa same area is limited, comprising: a volume structure reproducing meansfor reading volume structure recorded in a formatting process; achaining information reproducing means for reading the latest chaininginformation while reading in series a plurality of continuously recordedchaining information according to previously read volume structurecontent; a file structure reproducing means for reading file structureusing the read chaining information; and a file reproducing means forretrieving and reading a file using the read file structure.